Answer
MnO2 + 4 HCL -> MnCl2 + Cl2 + 2 H2O
Work Step by Step
Take the original equation and assign oxidation numbers to each of the reacting species in the chemical equation.
Determine which element is reduced and oxidized in the reaction.
Use coefficients to adjust the number of reactants and products so the total increase in oxidation number is equal to the total decrease in oxidation number.